Calques, also known as loan translations, are expressions that are translated literally from one language to another. Arabic subtitles of three English and French movies are utilized as a corpus for this study where their formation techniques are deduced and categorized as either lexical calques or structural calques following the categorisation proposed by Vinay and Darbelnet (1995: 32). Their calque quality is assessed and classified as good, or bad calques as proposed by Hervey & Higgins (2002, p.35) depending on their level of flouting to the TL norms. However, this study proposes adding a new category, to be referred to as ‘perfect calques’ to current binary good-bad categorization previously proposed by Hervey & Higgins (2002). Perfect calques are ones which would sound natural in Arabic to the extent that they would sweep unnoticeably into the stock of Arabic vocabulary. This study recommends that Arabic language authorities, government media bodies, academics, and translators should place importance on the issue of calquing in order to avoid language contamination.